The present invention relates to compositions for the treatment of injured, damaged or stressed cells, and in particular to a composition for promoting the repair of both prokaryotic and eukaryotic cells. The present invention also relates to methods for treating cells with the compositions of the present invention.
Environmental stresses due to heat, freezing, low pH, irradiation, trauma and the like can damage cellular membrane integrity, resulting in cell populations that require more exacting growth requirements for repair and proliferation. One characteristic of injured cells is their inability to tolerate growth conditions in which normal cells would multiply. Providing injured cells with an environment that promotes the repair of cellular membrane damage restores the injured cells to a sound physiological condition that enables the cells to tolerate the growth conditions in which normal cells flourish.
In the case of food pathogens, microorganisms damaged by food processing techniques can escape detection in food samples contaminated therewith. Providing microorganisms with an environment that restores the injured cells to sound physiological condition prevents the injured cells from escaping detection.
One impediment to the proliferation of damaged or stressed cells recognized by the prior art is the susceptibility of such cells to the accumulation of relatively low levels of hydrogen peroxide in the cell cytoplasm. Brewer, Appl. Environ. Biol., 34(6), 797-800 (1977), Rayman, Can. J. Microbiol., 24(7), 883-5 (1978) and McDonald, Appl. Environ. Microbiol., 45(2). 360-5 (1983) disclose the beneficial effects to injured cells of supplementing growth media with compounds that degrade hydrogen peroxide or block its formation, including sodium pyruvate.
The importance of antioxidants such as pyruvate in media for treating injured cells is also disclosed by D'Aoust, Appl. Environ. Microbiol., 35(3), 483-6 (1978), Alico, Appl. Environ. Microbiol., 51(4), 699-702 (1986) and Mackey, J. Appl. Bacteriol., 53(2), 233-42 (1982).
Park, Can. J. Microbiol., 23(5), 559-62 (1977) and D'Aoust, Appl. Environ. Microbiol., 35(3), 483-6 (1978) disclose growth media beneficial to injured cells. Supplementation of growth media with yeast extract was disclosed to nurture injured cells by Russell, Appl. Microbiol., 16(2), 335-9 (1986). Murthy, J. Food Microbiol., 4(4), 341-6 (1986) discloses supplementation of growth media with unsaturated fat to resuscitate injured cells. The importance of anaerobic conditions to the resuscitation of injured aerobic bacteria is disclosed by Allen, J. Bacteriol., 20, 417-39 (1930).